“I figure to have it paid for by Christmas,” says Ongstad, who paid $7,500 for the Environmental Protection Agency-certified, installed conversion, including a tank. “I was getting 12 miles per gallon and I’m hoping to get 8 or 9 or 10 with propane, because it’s not as many Btus (British thermal units) in a gallon of propane, but the propane is roughly half the cost of gasoline.”

Farmers have been using propane since the 1960s and 1970s, but maybe only 10 to 15 percent use propane in farm equipment, says Matt King, a certified installer and mechanic with Carburetion & Turbo Services Inc., of Shakopee, Minn., which installed Ongstad’s kit.

“For farmers, as much as they use diesel vehicles, they should really give propane a try,” King says. “Farming is up and down, but with propane we know the outcome — you’re going to save money.”

Ongstad isn’t sure how many farmers have propane conversion kits. He knows of a farmer in Steele, N.D., who has tractors and pickups and two-ton trucks on propane and it works very well in a carbureted system.

Carburetion & Turbo sells and installs a conversion kit for propane. The kit is made by IMPCO Automotive, a division of IMPCO Technologies Inc., and a subsidiary of Fuel Systems Solutions Inc., all based in Indiana.

King says the company can install about 100 per year. Most of the conversions have been for Minnesota customers. About 90 percent of the company’s business is selling natural gas and propane parts, so only about 10 percent is conversions, King says. It takes about three to four days to complete a conversion, and if a customer has an appropriate vehicle, appointments are being made about a month in advance.

Ongstad’s pickup has a 6.2-liter gasoline engine. He ordered it with a “propane package,” which has ports to run propane lines. All truck engines today have hardened valves and hardened valve seats and ports, to make them easily convertible, King says.

The “regulator” or “vaporizer” is bolted to the firewall, King says. The hose comes from the tank in the truck box. The regulator changes the fuel from a liquid to a gas form, which is injected into the manifold as gasoline would be. There are four injectors on each side of the intake manifold.

An engine is provided with an engine control module (ECM), also called a power control modulator (PCM). The truck has two of these — one for the gas and one for the propane.

“It’s fuel-injected and the computer tells everything what to do,” Ongstad says. “When you start it, if it’s cold, it’ll start on gasoline and when the temperature reaches 110 degrees, it’ll switch to propane. And if it’s warm in the summer it’ll start on propane.”

When it’s warm, it always prefers the propane, King says. The system can also be manually over-ridden with a switch in the cab.

Carburetion & Turbo sells propane motor fuel tanks in the 40-, 60-, 80- or 110-gallon sizes. Ongstad chose an 80-gallon propane tank. He can fill up to 80 percent of the tank, or about 60 useable gallons. Each gallon has a little less energy than a gallon of gasoline, he says. The standard gasoline tank on the Ford holds 32 gallons.

With the combination of the two fuels, Ongstad can go hundreds of miles, so the issue of finding a propane fill-up is not much of a problem. Ongstad typically will go to a propane dealer to get filled or will fill from a propane tank at home.

King says there is no regulation on propane prices. The best prices are available from propane companies that sell it in bulk, while retailers set up for bottle-filling might charge three times as much.